<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>图片上传</title>
  </head>
  <body>
    <input type="file" id="upload" />
    <script>
      // 获取 input 标签的 dom
      var input = document.getElementById('upload')
      // 监听它的变化
      input.addEventListener('change', function (e) {
        // 获取到上传的 file 对象
        var file = input.files[0]
        // 声明 FormData 实例 formData
        let formData = new FormData()
        // 添加实例属性 file
        formData.append('file', file)
        console.log('formData', formData)
        // 调用服务端上传接口。
        fetch('http://localhost:7001/api/upload', {
          method: 'POST',
          body: formData
        })
          .then(res => {
            if (res.ok) {
              console.log('success')
              return res.json()
            } else {
              console.log('error')
            }
          })
          .then(res => {
            console.log('res is', res)
          })
      })
    </script>
  </body>
</html>
